Strip stock feeder



March 15, 1966 A* F. GROLL STRIP STOCK FEEDER 2 Sheets-Sheet 1 Filed NOV. 26, 1962 INVENTOR. ALvm F. `@ROLL March 15, v1966 A. F. GRoLL STRIP STOCK FEEDER 2 Sheets-Sheet 2 INVENTOR ALVIN F. GROLL L t' M/f/g Mau/Ml,

Filed NOV. 26, 1962 United States Patent 3,240,044 STRIP STOCK FEEDER Alvin F. Groll, Box 347, Napoleon, Ohio Filed Nov. 26, 1962, Ser. No. 240,009 4 Claims. (Cl. 72-166) This invention relates to strip stock feeders.

Strip metal, usually steel, from which shapes are to be cut by power presses is supplied in tightly wound coils, the outside diameters of which may be four and one-half feet, more or less. While the metal of a coil usually is annealed it nevertheless is quite stiff and is set in the curvature of the coil. Hence, it is necessary to pass the strip through straightening mechanism which usually comprises a series of rollers that progressively reduce the curvature.

The coil to be unwound usually is supported in a cradle which carries the coil either on rotatable members that project axially into the center of the coil or rollers which lie beneath the coil and are engaged by the periphery of the coil. The rotatable members or the rollers in some installations are permitted to turn freely as the coil is unwound by pulling the strip metal therefrom. But in other installations at least one of the rotatable members or one of the rollers may be motor driven to turn the coil.

Because the metal of the strip is set in the curvature of the coil, the end of the strip must be forceably pulled or pried away from the periphery of the coil and threaded into the straightening mechanism. Hot rolled strip in particular takes a heavy set and creates problems by cracking when it is unrolled by the above procedure.

The objects of this invention are to improve strip stock feeders, to unroll strip metal and in particular hot rolled strip metal without cracking the metal, and to increase the coil traction in such feeders wherein the coils to be unwound are supported in cradles which lie beneath the coils and are engaged by the peripheries of the coils.

One embodiment of this invention enabling the realization of these objects is a strip stock feeder which is provided with means for applying a back or reverse bend to the strip as it cornes oif the coil, i.e., a bend opposite t the curvature of the coil. After the stock lifts free of the coil, pressure is applied to the strip to compress the outer surface and stretch the inner surface to avoid crimp and breakage. Such 'back or reverse bend should be as close to the tangent point where the strip cornes off the coil as possible and should be of a degree such that the back or reverse bend in itself does not injure the strip.

The strip stock feeder also is provided with means for increasing the coil traction, the feeder being of the type which supports the coil to `be unwound in a cradle which carries the coil on motor driven rollers that lie beneath the coil and are engaged by the periphery of the coil. Such means includes a pair of pressure rolls that force the coil to be unwound against the motor driven rollers with a constant pressure for all sizes of the coil. The increased traction is particularly important in rewind operations.

In accordance with the above, the principal feature of this invention resides in giving the reverse bend to the strip to avoid crimp and breakage.

Another feature resides in providing increased coil traction to avoid slippage between the coil and its cradle rollers.

The above and other objects and features of this invention will be appreciated more fully from the following detailed description when read with reference to the accompanying drawings wherein:

FIG. 1 is a side elevation in schematic form showing a strip stock feeder equipped with the means for applying a reverse bend to the strip as it cornes olf the coil and ICC the means for increasing the coil traction on its cradle rollers;

FIG. 2 is an enlarged vertical sectional view taken along the line 2w2 of FIG. l; and

FIG. 3 is an enlarged, fragmentary view of a portion of the mechanism shown in FIG. l.

Referring to the drawings, since the cradle may be of any desired type and may support coils by means of cones engaging the central coil opening or a conveyor belt or chain or a pair of rollers engaging the lower side of the periphery of the coil, the cradle is shown somewhat schematically, and will not be described herein in detail. Apparatus for feeding strip stock 10 from a stock coil 11 includes a pair of power driven coil supporting rollers 12 and 13 and a feeding and straightening device, which is not shown but which is shown in U.S. Patent No. 2,984,012, issued May 16, 1961 to Alvin F. Groll, that draws strip stock 10 from the coil 11 and delivers it to a punch press, power driven shears, or other similar machinery. The coil supporting rollers 12 and 13 and mechanism for driving these elements are mounted in a frame 14.

Power for driving the coil supporting rollers 12 and 13 is obtained from a motor (not shown) which drives a pinion shaft 1S carrying a pinion 16 which is meshed with a gear 17 on a rotatably mounted shaft 18 that in turn carries a gear 19. The gear 19 is meshed with a gear 20 on a rotatably mounted shaft 21 carrying a gear 22 which drives a gear 23 on a rotatably mounted shaft 24. A sprocket 25 is mounted on the shaft 24 and drives through a chain 26 to a sprocket 27 which turns as one with the coil supporting roller 12. 1f desired, the second coil supporting roller 13 may be connected -by a chain 28 to the coil supporting roller 12 so that both rollers are power driven and turn at the same speed, the chain 28 running around a sprocket 29 on the roller 12 and a sprocket 30 on the roller 13.

Because the metal of the strip is set in the curvature of the coil, the end of the strip must be forceably pulled or pried away from the periphery of the coil 11. A peeler 31 is provided for peeling the end of the strip 10 from the coil 11, such device being shown in detail in U.S. Patent No. 2,965,328, issued December 20, 1960 to Alvin F. Groll and therefore in FIG. 1 somewhat schematically. Pivoted at 32 to swing between the Walls of the frame 14 is a bail 33 consisting of a pair of arms which carry a blade 34 and a guide roller 235. A plunger rod 36 is pivoted at 37 to the bail 33 and extends into a hydraulic cylinder 38 which in turn is pivoted at 39 in the frame 14. Gravity is utilized to bring the blade 34 into contact with the exterior of the coil 11 as shown in FIG. 1 and after the strip 10 has been separated from the periphery of the coil and directed into the straightener hydraulic fluid is admitted to the lower end of the cylinder 38 to swing the bail 33 upwardly with the blade 34 out of engagement with the periphery of the coil 11 as shown in the above U.S. Patent No. 2,965,328.

Additional guide rollers 40 are mounted between the upright walls of the frame 14 and are in series with a curved guide sheet 41. Spaced from the guide rollers 40 and the guide sheet 41 are Ia cu-rved guide sheet 42 and a guide rib 43 to constitute -a path for the passage of strip material being unwound from the coil 11, such path being generally similar to that provided by the additional rollers and .guide ribs shown in the above U.S. Patent No. 2,965,328. The ends of the guide sheet 42 `and the guide rib 43 are spaced apart for a purpose hereinafter described.

The coil 11 when being -unwound is turned counterclockwise as viewed `in FIG. 1 and during rewind operations is turned clockwise. As the coil 11 becomes smaller during the unwinding operation it bears with less and less force on the coil supporting rollers 12 and 13 and, particularly during rewinding when the coil has been nearly used up, sometimes slips on the rollers 12 and 13. To prevent such slippage, a Ipair of pressure rollers 44 is provided for the coil 11 to obtain good traction.

The pressure rollers 44 are rotatable on shafts 45 carried by a bracket 46 which is xed to the lower end of a piston rod 47 extending into a hydraulic cylinder 48. The cylinder 48 is carried by a pin 49 supported between and journaled lin members 50 suitably supported in .turn Aby the frame 14. The pressure rollers 44 are equally spaced one on either side of the vertical centerline of the coil 11 as viewed in FIG. l so that they are in position to push the coil 11 squarely down upon the cradle rollers 12 and 13.

In the operation of the lpressure rollers 44, Huid is admitted to .the botto-rn of the hydraulic cylinder 4S to raise the rollers 44 before a new coil 11 is loaded upon the coil ysupporting rollers 12 and 13. Then, the cylinder 48 is -swung counterclockwise .about the axis of the pin 49 as viewed in FIG. 1 out of the way while the coil 11 is being loaded. Fluid is admitted to the top of the hydraulic cylinder 4S to force the pressure rollers 44 down against the periphery of the coil 11 pushing the coil 11 in turn down upon the cradle rollers 12 and 13 to increase the coil traction on such rollers 12 and 13 and prevent .the coil 11 slipping on the rollers 12 and 13. More and more fluid .is so admitted to the top of the hydraulic cylinder 48, as the coil 11 is used up and thus becomes smaller in outer diameter, that a constant pressure is applied by the pressure rollers 44 to the coil 11 for all sizes of coils 11.

The metal of the strip is set in the curvature of the `coil 11. Hot rolled strip in particular takes a heavy Set and creates problems by cracking when it is unrolled by means of the strip stock feeders of the prior art. To prevent such cracking, the strip stock feeder of the invention is provided with means for applying a back or reverse bend to the strip as it cornes off the coil, i.e., a bend opposite to the curvature of the coil.

The means for applying the back or reverse bend includes a continuously `driven roller 51 on a rotatably mounted shaft 52 which carries a sprocket 53. A chain 54 operatively connects the sprocket 53 to a sprocket 55 on a rotatably mounted shaft 56 which carries a gear 57 meshing with the gear 23 that serves also as a part of the above gear train from the motor pinion shaft to the sprocket 25 that drives the chain 28 for the coil supporting rollers 12 and 13. Hence, the coil supporting rollers 12 and 13 and the roller 51 turn together and in directions to all help advance the strip when the soil 11 is being unwound. The continuously driven roller 51 is juxtaposed to the end of the curved guide sheet 41. The continuously driven roller 51 acts as a backup roller for a reverse bend roller 58 which is located between the spaced apart ends of the guide rib 43 and the curved guide sheet 42. The reverse bend roller 58 is rotatably mounted on a shaft 59 carried by and between a pair of arms 60, one of which is shown in FIG. 1, mounted to pivot about the axis of a pivot pin 61 suitably supported by the frame 14. The ends of the arms 60 remote from the pivot pins 61 are pivoted at 62 to the end `of a piston rod 63 extending intoa hydraulic cylinder 64, the cylinder 64 being mounted on a pivot pin 65 pivotally mounted by and between ears 66 of the frame 14. Fluid is admitted to the left hand end of the hydraulic cylinder 64 as viewed in FIG. 1 to pivot the reverse bend roller 58 counterclockwise about the axis of the pivot pin 61 to make it easy to thread the strip 10 between the rollers 51 and 58 and to provide an adjustment for various thicknesses of strip. Fluid is admitted to the other end of the hydraulic cylinder 64 to pivot the reverse bend roller 58 clockwise about the axis of the pivot pin 61 until it pushes the metal strip 10 into engagement with the backup roller 51 to put the reverse bend into the strip.

The back or reverse bend should be close to the tangent point where the strip comes off the coil 11 and should be of a degree such that the bend in itself does not injure the strip. It is known that a sharp bend of about degrees around a short radius roll causes a series of minute fractures or surface checks. As shown in FIG. l, the distance from such tangent point to such reverse bend is less than the outside diameter of the coil 11. The coil 11 is about as large as the feeder can accommodate. Preferably the distance from such tangent point to such reverse bend should be less than the outside diameter of the coil 11 before any of the coil is unwound. The outside diameter of the unwound coil 11 may be four and one-half feet, more or less. In no case should the distance from such tangent point to such reverse bend be substantially more than the outside diameter of the unwound coil or otherwise the strip may crack before reaching the reverse bend station.

The strip 10 comes off the coil 11 at the tangent point and is guided around the guide roller 35 on the peeler 31 into close juxtaposition with the guide rib 43. The strip 1t) then approaches the bite between the backup roller 51 and the reverse bend roller S at an acute angle, as shown in FIG. 3, to a line A connecting the axes of rotation of such rollers 51 and 58. A broken line B is shown in FIG. 3 as an extension of the unbent strip 10 to better illustrate the approach angle which the strip makes with line A. A normal line C drawn from the axis of rotation of the reverse bend roller 58 to the unbent strip 10 is offset and behind relative to a normal line D drawn from the axis of rotation of the backup roller 51 to the line B, i.e., to the extension of the strip 10 before it receives its back or reverse bend. Since the perpendicular lines C and D, i.e., perpendicular to the unbent strip, are offset as shown, the strip 10 bends around the reverse bend roller 58. This back or reverse bend is opposite to the curvature of the coil 11. If such perpendicular lines C and D coincided with line A, the strip 10 merely would be pinched between the rollers 51 and 58 with no reverse bend occurring. The strip 10 then continues upward between the guides 41 and 42 until it rests on the guide rollers 40 under the influence of gravity and proceeds as indicated by the arrow in FIG. 1.

It is to be understood that the above description is illustrative of this invention and that various modifications thereof can be utilized without departing from its spirit and scope.

Having described the invention, I claim:

1. In a strip stock feeder for stock having a permanent set in the coil, in combination, cradle means. for supporting a coil of strip at at least two positions on its outer periphery spaced on opposite sides of the vertical projection of the center of gravity of said coil and extending across the width of the stock, a first roller having its longitudinal axis parallel to that of a coil supported by said cradle means and positioned to engage the inner surface of the strip stock at a position adjacent the coil along a path for said stock which carries said stock from the coil supporting means of said cradle most proximate said roller to said roller with a curvature less than the unrestrained set of said stock and at which f the stresses with the stock are less than its elastic limit,

a power source operatively connected to the cradle means to rotate said coil and to the rst roller to rotate it about its longitudinal axis, a second roller mounted to rotate about its longitudinal axis and mounted with its longitudinal axis parallel to said rst roller to rock about a second axis parallel to said longitudinal axis, said second roller being positioned to rock into engagement with said strip stock along a path intersecting said first roller, said second roller being positioned to have its point of tangency to said stock path between said cradle means most proximate said first roller and the point of taugency of said rst roller to said stock path, and means to force said second roller about said second axis and toward said rst roller whereby said stock is engaged on opposed faces across its width by said first and second rollers and is iiexed beyond its elastic limit and short of its yield point as it is advanced between said first and second rollers to impart a reverse bend opposite the set in the coil.

2. A combination according to claim 1 wherein said stock path length between said cradle means support position most proximate said iirst roller and the line of tangency of said iirst roller to said stock path is less than the maximum outer -diameter of said coil.

3. A combination according to claim 1 wherein a third roller having a longitudinal axis parallel to that of said first roller engages the inner face of the uncoiled strip stock at a point along said stock path between said cradle means support position most proximate said lirst roller and the iirst roller.

4. In a strip stock feeder for stock having a permanent set in the coil, in combination, cradle means for supporting a coil of strip at at least two positions on its outer periphery spaced on opposite sides of the vertical projection of the center of gravity of said coil and extending across the width of the stock, a i'irst roller having its longitudinal axis parallel to that of a coil supported by said cradle means and positioned to engage the inner surface of the strip stock at a position adjacent the coil along a path for said stock wkuch carries said stock from the coil supporting means of said cradle most proximate said roller to said roller with a curvature less than the unrestrained set of said stock and at which the stresses with the stock are less than its elastic limit, said stock path between said cradle means support position most proximate said first roller and the line of tangency of said rst roller to said stock path is less than the maximum outer diameter of said coil, a power source operatively connected to the cradle means to rotate said coil and to saidiirst roller to rotate it about its longitudinal axis, a second roller mounted to rotate about a longitudinal axis parallel to that of said first roller and to pinch said strip stock against said iirst roller, the line of common tangency of said iirst and second rollers falling on the coil side of said strip stock path and defining a small acute angle with said strip stock path whereby said stock is held in compression between said rst and second rollers in the region between the coil and rollers in which it is stressed the maximum and is stressed in said region beyond its elastic limit and short of its yield point.

References Cited by the Examiner UNITED STATES PATENTS 2,246,840 6/1941 Crane et al 153-54 2,494,399 1/1950 McCleary 153-54 2,750,984 6/1956 Miller 15354 3,079,976 3/1963 Ranney 153-54 CHARLES W. LANHAM, Primary Examiner. 

1. IN A STRIP STOCK FEEDER FOR STOCK HAVING A PERMANENT SET IN THE COIL, IN COMBUSTION, CRADLE MEANS FOR SUPPORTING A COIL OF STRIP AT AT LEAST TWO POSITIONS ON ITS OUTER PERIPHERY SPACED ON OPPOSITE SIDES OF THE VERTICAL PROJECTION OF THE CENTER OF GRAVITY OF SAID COIL AND EXTENDING ACROSS THE WIDTH OF THE STOCK, A FIRST ROLLER HAVING ITS LONGITUDINAL AXIS PARALLEL TO THAT OF A COIL SUPPORTED BY SAID CRADLE MEANS AND POSITIONED TO ENGAGE THE INNER SURFACE OF THE STRIP STOCK AT A POSITION ADJACENT THE COIL ALONG A PATH FOR STOCK WHICH CARRIES SAID STOCK FROM THE COIL SUPPORTING MEANS OF SAID CRADLE SAID PROXIMATE SAID ROLLER TO SAID ROLLER WITH A CURVATURE LESS THAN THE UNRESTRAINED SET OF STOCK AND AT WHICH THE STRESSES WITH THE STOCK ARE LESS THAN ITS ELASTIC LIMIT, A POWER SOURCE OPERATIVELY CONNECTED TO THE CRADLE MEANS TO ROTATE SAID COIL AND TO THE FIRST ROLLER TO ROTATE IT ABOUT ITS LONGITUDINAL AXIS, A SECOND ROLLER MOUNTED TO ROTATE ABOUT ITS LONGITUDINAL AXIS AND MOUNTED WITH ITS LONGITUDINAL AXIS PARALLEL TO SAID FIRST ROLLER TO ROCK ABOUT A SECOND AXIS PARALLEL TO SAID LONGITUDINAL AXIS, SAID SECOND ROLLER BEING POSITIONED TO ROCK INTO ENGAGEMENT WITH SAID STRIP STOCK ALONG, A PATH INTERSECTING SAID FIRST ROLLER, SAID SECOND ROLLER BEING POSITIONED TO HAVE ITS POINT OF TANGENCY TO SAID STOCK PATH BETWEEN SAID CRADLE MEANS MOST PROXIMATE SAID FIRST ROLLER AND THE POINT OF TANGENCY OF SAID FIRST ROLLER TO SAID STOCK PATH, AND MEANS TO FORCE SAID SECOND ROLLER ABOUT SAID SECOND AXIS AND TOWARD SAID FIRST ROLLER WHEREBY SAID STOCK IS ENGAGED ON OPPOSED FACES ACROSS ITS WIDTH BY SAID FIRST AND SECOND ROLLERS AND IS FLEXED BEYOND ITS ELASTIC LIMIT AND SHORT OF ITS YIELD POINT AS IT IS ADVANCED BETWEEN SAID FIRST AND SECOND ROLLERS TO IMPART A REVERSE BEND OPPOSITE THE SET IN THE COIL. 